Fire crews were called to a tobacconist at Coburg, in Melbourne's north, about 4.30am on Friday following reports it was engulfed by flames.
Investigators said offenders broke into the Sydney Rd store and set it alight.
The shopfront received extensive damage but firefighters were able to stop the blaze from spreading to adjoining businesses.
Firefighters were called to the Sydney Rd shop early on Friday after reports it was alight. (James Ross/AAP PHOTOS)
Police are also investigating a ramming and attempted arson at a tobacco store in Footscray, Melbourne's west, just after 3am.
A vehicle rammed the front security roller shutter of the store and the occupants unsuccessfully attempted to set fire to it before fleeing.
Investigators are treating both overnight incidents as targeted attacks.
Fire Rescue Victoria commander Paul Eckholdt said while there were no injuries to members of the public or firefighters, it was only a matter of time before someone was hurt.
"It is a worry for Fire Rescue Victoria with the amount of these fires that are occurring," he told ABC News on Friday.
"We are worried at some point it may involve injuries to the public or firefighters."
Fire crews were able to stop the Coburg shop fire from spreading to neighbouring businesses. (James Ross/AAP PHOTOS)
A man and woman will face court on Friday after being charged over incidents in Melbourne, Mildura and Ballarat, including an arson attack on a Mildura tobacco store.
Police allege the duo were in a car that rammed the front window of the tobacconist shop on Tuesday before they poured accelerant into the building and set it alight.
In May Victoria Police warned landlords to think twice about leasing shopfronts to businesses that may be targeted.
Police said they had investigated 60 arson attacks at tobacco or vape stores across the state in the past 15 months.
Investigators believe those firebombings were linked to conflict between crime syndicates over illegal tobacco.
Other venues including gyms, private homes, restaurants and cars have also been targeted.
Plans by the state government to introduce legislation to establish a tobacco retailer and wholesale licensing scheme have been welcomed by Victoria Police.
That legislation is expected to be introduced in the second half of 2024.
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